It's based on what Donald Trump (or any other US president, should it come to that) says, not on any evidence or ground truth beyond that.
The are motives for lying on this - for a start, if a president knows definitively they're going to say it, it's a free 81% return. Secondly, it's a pretty big dead cat to throw on the table to distract from any scandal and/or to keep themselves in the news cycle on a different topic.
It's based on what Donald Trump (or any other US president, should it come to that) says, not on any evidence or ground truth beyond that.
The are motives for lying on this - for a start, if a president knows definitively they're going to say it, it's a free 81% return. Secondly, it's a pretty big dead cat to throw on the table to distract from any scandal and/or to keep themselves in the news cycle on a different topic.